不同播期冬小麦株型构建及其生育特征

针对黄淮平原中部冬小麦区秋季旱涝频发导致小麦播种推迟的现状，设计冬小麦10月15日(适期播种)、10月30日(中晚期播种)、11月15日(晚期播种)、11月30日(超晚期播种)、2月15日(早春播种)和3月1日(春播)6个播期，研究不同播期冬小麦株型构建及生长发育特征.结果表明： 随着冬小麦播期的推迟，其生长发育进程加快，早春播种和春播与适期播种相比生育期缩短115~130 d；10月30日(中晚期播种)之后的5个播期与适期播种相比株高降低，成穗数和有效小穗数减少；迟播小麦的叶位下移，冠层空间降低，叶面积减少；收获指数随播种期推迟由0.46(适期播种)提高到0.53(春播)；冬小麦产量随播种期推迟显著下降，减产幅度最高达43.6%；冬小麦春季播种未经过冬季和早春阶段的自然低温处理，无春化过程依然可形成产量.

Shoot type morphology and growth characteristics of winter wheat sown at different dates

Aiming at the delayed sowing of winter wheat induced by the drought and water logging often occurred in Huanghuai Plains of China, six sowing dates (15 October, normal sowing; 30 October, moderate delay; 15 November, delay; 30 November, seriously delay; 15 February, early spring sowing; and 1 March, spring sowing) were designed to investigate the effects of different sowing dates on the shoot type morphology and growth characteristics of winter wheat. With the delay of sowing date, the winter wheat grew and developed faster, and the growing period of the wheat sown in early spring and spring was 115-130 days shorter than that with normal sowing. As compared with those of the wheat with normal sowing, the shoot height, spike number per unit area, and productive spikelets per unit ear of the wheat sown delayed had a decrease, leaf position and canopy moved down, and leaf area reduced. When the sowing was delayed from the date 15 October (normal sowing) to 1 March (spring sowing), the harvest index increased from 0.46 to 0.53. Delaying sowing date also resulted in the significant reduction of grain yield, with the maximum decrement as high as 43.6%. The spring sown winter wheat not going through vernalization could still form yield.